title: Differentiated mTOR but not AMPK signaling after strength vs endurance exercise in training-accustomed individuals.
abstract: The influence of adenosine mono phosphate (AMP)-activated protein kinase (AMPK) vs Akt-mammalian target of rapamycin C1 (mTORC1) protein signaling mechanisms on converting differentiated exercise into training specific adaptations is not well-established. To investigate this, human subjects were divided into endurance, strength, and non-exercise control groups. Data were obtained before and during post-exercise recovery from single-bout exercise, conducted with an exercise mode to which the exercise subjects were accustomed through 10 weeks of prior training. Blood and muscle samples were analyzed for plasma substrates and hormones and for muscle markers of AMPK and Akt-mTORC1 protein signaling. Increases in plasma glucose, insulin, growth hormone (GH), and insulin-like growth factor (IGF)-1, and in phosphorylated muscle phospho-Akt substrate (PAS) of 160 kDa, mTOR, 70 kDa ribosomal protein S6 kinase, eukaryotic initiation factor 4E, and glycogen synthase kinase 3a were observed after strength exercise. Increased phosphorylation of AMPK, histone deacetylase5 (HDAC5), cAMP response element-binding protein, and acetyl-CoA carboxylase (ACC) was observed after endurance exercise, but not differently from after strength exercise. No changes in protein phosphorylation were observed in non-exercise controls. Endurance training produced an increase in maximal oxygen uptake and a decrease in submaximal exercise heart rate, while strength training produced increases in muscle cross-sectional area and strength. No changes in basal levels of signaling proteins were observed in response to training. The results support that in training-accustomed individuals, mTORC1 signaling is preferentially activated after hypertrophy-inducing exercise, while AMPK signaling is less specific for differentiated exercise.
authors.affiliation: Department of Sport Science, Aarhus University, Aarhus, Denmark. vissing@sport.au.dk
authors.forename: K
authors.initials: K
authors.lastname: Vissing
authors.forename: S  L
authors.initials: S
authors.lastname: McGee
authors.forename: J
authors.initials: J
authors.lastname: Farup
authors.forename: T
authors.initials: T
authors.lastname: Kjølhede
authors.forename: M  H
authors.initials: M
authors.lastname: Vendelbo
authors.forename: N
authors.initials: N
authors.lastname: Jessen
mesh_terms: D055372:AMP-Activated Protein Kinases / Q000097:blood / Q000378:metabolism*; D000103:Acetyl-CoA Carboxylase / Q000378:metabolism; D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D017362:Cyclic AMP Response Element-Binding Protein / Q000378:metabolism; D039561:Eukaryotic Initiation Factor-4E / Q000378:metabolism; D015444:Exercise / Q000502:physiology*; D020690:GTPase-Activating Proteins / Q000378:metabolism; D038362:Glycogen Synthase Kinase 3 / Q000378:metabolism; D013006:Growth Hormone / Q000097:blood; D006339:Heart Rate; D006655:Histone Deacetylases / Q000378:metabolism; D006801:Humans; D007328:Insulin / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D008279:Magnetic Resonance Imaging; D008297:Male; D000076222:Mechanistic Target of Rapamycin Complex 1; D046912:Multiprotein Complexes / Q000097:blood / Q000378:metabolism*; D053580:Muscle Strength / Q000502:physiology; D018482:Muscle, Skeletal / Q000033:anatomy & histology / Q000378:metabolism*; D010101:Oxygen Consumption; D010766:Phosphorylation; D055070:Resistance Training; D038762:Ribosomal Protein S6 Kinases, 70-kDa / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology*; D058570:TOR Serine-Threonine Kinases / Q000097:blood / Q000378:metabolism*; D055815:Young Adult
chemical_list: D001786:Blood Glucose; D017362:Cyclic AMP Response Element-Binding Protein; D039561:Eukaryotic Initiation Factor-4E; D020690:GTPase-Activating Proteins; C583557:IGF1 protein, human; D007328:Insulin; D046912:Multiprotein Complexes; C518767:TBC1D4 protein, human; D007334:Insulin-Like Growth Factor I; D013006:Growth Hormone; D000076222:Mechanistic Target of Rapamycin Complex 1; D038762:Ribosomal Protein S6 Kinases, 70-kDa; D058570:TOR Serine-Threonine Kinases; D038362:Glycogen Synthase Kinase 3; C448021:glycogen synthase kinase 3 alpha; D055372:AMP-Activated Protein Kinases; C404500:HDAC5 protein, human; D006655:Histone Deacetylases; D000103:Acetyl-CoA Carboxylase